Effects Of Different Low-dose Dexmedetomidine On The Quality Of Recovery Under General Anesthesia In Patients Undergoing Gynecological Laparoscopic Surgery

Objective:To study the effect of continuous intravenous infusion of dexmedetomidine at different low doses on quality of anesthesia and adverse events in gynecological laparoscopic surgery under elective general anesthesia,and to evaluate the optimal effective dose of continuous intravenous infusion of dexmedetomidine at anesthesia maintenance stage to improve quality of anesthesia.Methods:From June 2019 to December 2019,80 patients who planned to undergo Laparoscopic gynecologic surgery under general anesthesia in the second hospital of Hebei medical university were randomly divided into 4 groups,control group 0.9%saline injection group（D1 group）,Dexmedetomidine0.2ug/kg/h injection group（D2 group）,0.3ug/kg/h injection group（D3 group）and 0.4ug/kg/h injection group（D4 group）.After induction of anesthesia,either Dexmedetomidine or normal saline was injected through a micro infusion pump at the target injection rate according to the patient’s body weight.The hemodynamic parameters,anesthetic dosage,bispectral index（BIS）,pulse oxygen saturation（Sp O₂）,cough response degree,Riker sedation-agitation score（SAS）,recovery time and adverse events were recorded.Results:1. There was no significant difference in general condition between the four groups（P>0.05）.2. Comparison of hemodynamic parameters:Heart rate（HR）:Compare with baseline,the heart rate was significantly increased in group D1,D2 and D3 at extubation;It was significantly increased in group D1 1min and 3min after extubation.However,it was significantly reduced in D4 group 15min after tracheal extubation.There was a significant difference between group D1 and group D4 at extubation（P<0.05）.Systolic blood pressure（SBP）:There was no significant fluctuation in dexmedetomidine groups（P>0.05）,while the difference between tracheal extubation and 1min after tracheal extubation was statistically significant（P<0.05）.The control group was significantly higher than the D3 and D4groups at extubation（P<0.05）.At 1min,3min,5min and 10min after tracheal extubation,the D4 group was significantly lower than the control group（P<0.05）.Diastolic blood pressure（DBP）:there was no statistically significant difference among the four groups（P>0.05）.Mean arterial pressure（MAP）:there was no significant fluctuation in the four groups（P>0.05）.The D4 group was significantly lower than the control group at tracheal extubation and 1min,5min and 10min after tracheal extubation（P<0.05）.3. The mean reduction of propofol and remifentanil in D3 and D4 groups was significantly different from that in D1 and D2 groups（P<0.05）.4. The respiratory recovery time,extubation time and awakening time of the D3 group and the D4 group were significantly longer than that of the control group（P<0.05）,while the differences between the D3 group and the D4 group were not statistically significant（P>0.05）.The respiratory recovery time and awakening time in the D2 group were significantly lower than those in the D4 group（P<0.05）.5. There was no significant difference in the incidence of choking between the four groups（P>0.05）.However,the incidence of grade 1 and grade 2 in the 20 patients in the control group was significantly lower than that in the D2,D3 and D4 groups（P<0.05）.6. There were significant differences in Riker sedative-agitation scores between the groups（P<0.05）.The sedative-agitation score of D4 group was significantly lower than that of D1 and D2 group（P<0.05）.The difference between the D3 group and the control group was statistically significant（P<0.05）.There was no statistically significant difference in the incidence of good sedation between the four groups（P>0.05）,but there was a statistically significant difference in the incidence of patients with deep sedation between the four groups（P<0.05）.The D4 group were significantly higher than the D1group（P<0.05）.The incidence of postoperative restlessness was significantly different among the groups（P<0.05）.The incidence of agitation in D3 and D4groups was significantly lower than that in D1 and D2 groups（P<0.05）.7. BIS in four groups of patients:there was no statistically significant difference among the four groups（P>0.05）.8. There was no statistically significant difference in the incidence of various adverse events among the four groups（P>0.05）.Compared with the control group,the incidence of tachycardia and hypotension in the D2,D3 and D4 groups was gradually lower,and the incidence of hypotension was gradually increased.There was no significant difference in the incidence of bradycardia and hypertension among the four groups（P>0.05）,and no adverse reactions such as severe bradycardia,severe hypotension,respiratory depression,laryngospasm,bronchospasm,and decreased pulse oxygen saturation occurred in any of the four groups.Conclusions:Continuous intravenous infusion of dexmedetomidine at low dose during anesthesia maintenance period improved the quality of general anesthesia recovery in gynecological laparoscopic surgery.Dexmedetomidine 0.3ug/kg/h intravenous infusion group to a certain extent reduced the stress response during the recovery period,reduced the occurrence of adverse events,and also reduced the dosage of anesthetics.However,its synergistic effect with other anesthetics to some extent deepens the sedation level and prolongs the recovery time,which is not clinically significant.